JPS6131175Y2 - - Google Patents

Description

[Detailed description of the invention] The purpose of this invention is to maintain good fuel injection and maintain high combustion performance even during continuous high-speed, high-load operation with respect to a fuel injection device for a water-cooled horizontal direct injection engine. do.

Conventionally, as shown in FIG. 4, a fuel injection device for a water-cooled horizontal direct injection engine has a cylinder head 21 fixed to the front end wall of a crankcase 20, and an integrally cast nozzle inserted through a head jacket 22 of the cylinder head 21. A fuel injection nozzle 24 is inserted into the boss 23 and fixed.

However, the water inlet 26 that communicates the head jacket 22 and the radiator 25 is restricted;
And, since the wall 27 of the nozzle insertion boss 23 is thick, the heat of the fuel injection nozzle 24 is difficult to dissipate.
If the engine is operated at high speed and under high load for a long period of time, the fuel injection nozzle 24 will be overheated due to insufficient cooling, and the fuel in the nozzle 24 will carbonize, clogging the nozzle nozzle or distorting the direction of fuel injection, reducing fuel performance. Because of this, the engine could not be operated continuously at high speed and high load for long periods of time.

The present invention was proposed in order to eliminate the above-mentioned drawbacks, and by forming the cylinder and cylinder head integrally, the cylinder jacket and head jacket are formed in series, and the upper opening of the head jacket is enlarged to the lower part of the radiator. The cylinder jacket is opened to allow a large amount of cooling water to flow through the cylinder jacket and the head jacket, and the cooling water that flows into the head jacket flows through the rising gap between the intake and exhaust port walls and rises through the thin nozzle insertion tube. The fuel injection nozzle inserted and fixed therein is strongly cooled to prevent carbonization of the fuel inside the nozzle.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a side view of a water-cooled horizontal diesel engine. In this engine E, a radiator 2 and a fuel tank 3 are mounted and fixed in line above a crankcase 1, and a cylinder head 4 is formed integrally with the crankcase 1 by casting.

A cylinder liner 6 in which a piston 5 is slidably housed is supported in the crankcase 1, and a cylinder jacket 7 formed in a cylinder block C is disposed around the cylinder liner 6.
Further, a head jacket 8 is formed inside the cylinder head 4, and the cylinder jacket 7 and the head jacket 8 are formed in series.

The upper part of the cylinder jacket 7 is largely open and communicates with the lower part of the radiator 2. The front part 7a of the upper part of the cylinder jacket 7 is enlarged toward the front and extends to the upper side of the head jacket 8, and this enlarged cylinder jacket part 7b
Open the top surface 8b of the head jacket 8 on the bottom surface of the cylinder jacket 7 and the head jacket 8.
The upper part communicates with the other parts. The cylinder jacket 7 also communicates with the lower part of the head jacket 8 (see FIG. 2).

A fuel injection nozzle 9, an intake valve 11, and an exhaust valve 10 are inserted into the cylinder head 4 so as to pass through a head jacket 8 from the outside.

As shown in the longitudinal sectional front view of FIG. 3, these intake valves 11, exhaust valves 10, and fuel injection nozzles 9 are arranged in such a way that the intake valves 11 and exhaust valves 10 are arranged horizontally on both sides without vertically overlapping each other, and the intake ports 12 and exhaust port 1
A fuel injection nozzle 9 is positioned above a cooling water rising gap S formed between port walls 14 and 15 of No. 3.

This fuel injection nozzle 9 has a thin nozzle insertion tube 19 inserted into the tube insertion holes 17 and 18 formed in the front end wall 8a of the head jacket 8 and the front end wall 16a of the combustion chamber 16.
is inserted and fixed, and the fuel injection nozzle 9 is inserted and fixed into the nozzle insertion cylinder 19.

The fuel injection nozzle 9 installed in this way is strongly cooled by the cooling water flowing through the head jacket 8, especially the cooling water flowing through the water rising gap S between the port walls 14 and 15 of the intake and exhaust ports 12 and 13, and the fuel injection nozzle 9 is strongly cooled due to overheating. Carbonization of the fuel within the injection nozzle 9 can be prevented, and good fuel injection can always be maintained.

The present invention is configured and operates as described above, and thus has the following effects.

That is, the cylinder and cylinder head are integrally cast, the cylinder jacket and the head jacket are formed in series, and the upper opening of the head jacket is opened directly facing the lower part of the radiator, so that it is easy to remove the head jacket from the cylinder jacket. The flow resistance of the cooling water that returns to the radiator is small, and a large amount of cooling water can be circulated to powerfully cool the combustion chamber. Since the fuel injection nozzle closely inserted and fixed through the nozzle insertion tube is strongly cooled, it is possible to prevent the fuel in the fuel injection nozzle from being overheated and carbonized. Thereby, fuel injection from the fuel injection nozzle can be maintained well, and the engine can be continuously operated at high speed and under high load even for a long period of time.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the present invention, with Figure 1 being a side view of a water-cooled horizontal direct injection engine, Figure 2 being a side view of the main parts, and Figure 3 being a longitudinal sectional front view of the cylinder head. FIG. 4 is a diagram corresponding to FIG. 2 showing a conventional example. E...Engine, S...Water rise gap, 4...Cylinder head, 6...Cylinder (cylinder liner), 7...Cylinder jacket, 8...Head jacket, 8a...Front end wall of 8, 14.1
5. Intake/exhaust port wall, 16. Combustion chamber, 16
a... 16 front wall, 17, 18... nozzle insertion hole, 19... nozzle insertion tube.

Claims (1)

[Scope of utility model registration request] The cylinder head 4 is integrally cast in the front part of the cylinder 6 of the water-cooled horizontal fuel direct injection engine E, and the upper surface of the cylinder jacket 7 surrounding the cylinder 6 is opened, and the upper front part inside the cylinder jacket 7 is formed. 7a is expanded to the upper side of the head jacket 8 of the cylinder head 4, and the upper surface 8 of the head jacket 8 is attached to the bottom surface of this expanded cylinder jacket portion 7b.
b are opened and communicated with each other, and the intake/exhaust ports 12 and 13 are connected to each other in the intermediate height part of the port walls 14 and 15 of the intake and exhaust ports 12 and 13 in a vertical cross-sectional view from the front of the head jacket 8 in a state where they do not overlap in the vertical direction. One side is provided on one lateral side and the other is provided on the other lateral side, and a water rising gap S is formed between the opposing port walls 14 and 15, and the combustion chamber 1 is formed above this water rising gap S.
The insertion holes 17 and 18 are formed in the front end wall 16a of the head 6 and the front end wall 8a of the head jacket 8.
18, insert and fix the nozzle insertion tube 19,
This fuel injection device for a water-cooled horizontal direct injection engine is characterized in that the nozzle insertion tube 19 is positioned directly above the water rising gap S, and the fuel injection nozzle 9 is closely inserted into the nozzle insertion tube 19.